The disclosure generally relates to an analog-to-digital converter and, more particularly, to a pipelined analog-to-digital converter that can be shared by different circuit stages.
Operational amplifiers are typically employed in a conventional pipelined analog-to-digital converter, but the overall performance or operating speed of the pipelined analog-to-digital converter is typically restricted by the response speed of the operational amplifiers. As is well known in related art, the length of time required for charging or discharging the feedback capacitors within the operational amplifier has a great influence to the response speed of the operational amplifier. It would be difficult to increase the overall performance or operating speed of the conventional pipelined analog-to-digital converter if the required time for charging or discharging the feedback capacitors within the operational amplifiers cannot be substantially reduced.